Magnetic, Optical and I-V Characteristics of MoO3 thin films

Abstract

Molybdenum trioxide (MoO3) thin films with cobalt concentration were grown on quartz and n-type Si (100) by thermal evaporation deposition technique. Then the films were thermally annealed for 2 hours under normal environment. The structure is analyzed by X-Ray Diffraction (XRD) to confirm the orthorhombic α-MoO3 phase confirming the crystallinity of thin films. Furthermore, the morphological study is done by Scanning Electron Microscope (SEM) to confirm granular shaped interconnected films. Thicknesses of films are determined by Ellipsometry which vary from 40nm to 140nm with the decrease in Cobalt concentration of thin films. Modifications in optical properties due to the doping of Cobalt in MoO3 thin films are studied in terms of transmittance data and Taucs plot. All films represent direct band gap transitions. The band-gap of MoO3 comes out be 3.32eV from the Taucs plot. A slight change in the band-gaps is found for various films with different concentration. Vibrating Sample Magnetometer (VSM) results studied at the room temperature confirm the introduced magnetic property as well as the hysteresis loop for the Cobalt doped MoO3 thin films.